TRANSMISSION LINES AND WAVEGUIDES EC2305 NOVEMBER/DECEMBER 2010 ANNA UNIV PREVIOUS YEAR QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2010

Fifth Semester

Electronics and Communication Engineering

EC 2305 � TRANSMISSION LINES AND WAVEGUIDES

(Regulation 2008)

Time : Three hours Maximum : 100 Marks

Answer ALL questions

PART A � (10 � 2 = 20 Marks)

1. A constant-K T-section high pass filter has a cutoff frequency of 10 KHz. The design impedance is 600 ohms. Determine the value of L.

2. What are the advantages of m-derived filters?

3. Define delay distortion.

4. Write the expressions for the phase constant and velocity of propagation for telephone cable.

5. A lossless line has a characteristic impedance of 400 ohms. Determine the standing wave ratio if the receiving end impedance is 800 +j 0.0 ohms.

6. Write the expressions for the input impedance of open and short circuited dissipationless line.

7. Define the cutoff frequency for the guided waves.

8. For a frequency of 6 GHz and plane separation of 3 cm, find the group and phase velocities for the dominant mode.

9. Calculate the cutoff wavelength for the TM11 mode in a standard rectangular waveguide if a = 4.5 cm.

10. Give the applications of cavity resonators.

PART B � (5 � 16 = 80 Marks)

11. (a) (i) Design a m-derived T-section low pass filter having a cutoff frequency (fc) of 5000 Hz and a design impedance of 600 ohms. The frequency of infinite attenuation is 1.25 fc. (8)

(ii) Draw and explain the operation of crystal filters. (8)

Or

(b) (i) Design a constant-K T-section bandpass filter with cutoff frequencies of 1 KHz and 4 KHz. The design impedance is 600 ohms.

(8)

(ii) Draw a constant-K T-section band elimination filter and explain the operation with necessary design equations. (8)

12. (a) (i) A transmission line has the following per unit length parameters : L = 0.1� H, R =5 ohms, C = 300 pF and G = 0.01 mho. Calculate the propagation constant and characteristic impedance at 500 MHz. (8)

(ii) Derive the conditions required for a distortionless line. (8)

Or

(b) (i) The characteristic impedance of a uniform transmission line is 2309.6 ohms at a frequency of 800 MHz. At this frequency, the propagation constant is 0.054(0.0366 + j 0.99). Determine Rand L.

(6)

(ii) Explain the reflection on lines not terminated in characteristic impedance with phasor diagrams. Define reflection coefficient and reflection loss. (10)

13. (a) (i) Draw and explain the operation of quarter wave line. (8)

(ii) It is required to match a 200 ohms load to a 300 ohms transmission line to reduce the SWR along the line to 1. What must be the characteristic impedance of the quarter wave transformer used for

this purpose if it is directly connected to the load? (4)

(iii) What are the drawbacks of single stub matching and open circuited stubs? (4)

Or

(b) (i) Draw and explain the principle of double stub matching. (8)

(ii) A UHF lossless transmission line working at 1 GHz is connected to an unmatched line producing a voltage reflection coefficient of 0.5(0.866 + j 0.5). Calculate the length and position of the stub to match the line. (8)

14. (a) (i) Explain the transmission of TE waves between parallel perfectly conducting planes with necessary expressions and diagrams for the field components. (12)

(ii) A TEM wave at 1 MHz propagates in the region between conducting planes which is filled with dielectric material of r � = 1 and r e = 2. Find the phase constant and characteristic wave impedance. (4)

Or

(b) (i) Explain the reasons for the attenuation of TE and TM waves between parallel planes with necessary expressions and diagrams. (10)

(ii) Write a brief note on the manner of wave travel and their velocities between parallel planes. (6)

15. (a) (i) Discuss the propagation of TM waves in a rectangular waveguide with relevant expressions and diagrams for the field components. (10)

(ii) A rectangular waveguide measuring a = 4.5 cm and b = 3 cm internally has a 9 GHz signal propagated in it. Calculate the guide wavelength, phase and group velocities and characteristic impedance for the dominant mode. (6)

Or

(b) Explain the propagation of electromagnetic waves in a cylindrical waveguide with suitable expressions.(16)

EC2305 TRANSMISSION LINES AND WAVEGUIDES NOVEMBER/DECEMBER 2010 ANNA UNIVERSITY QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2010

Fifth Semester

Electronics and Communication Engineering

EC 2305 � TRANSMISSION LINES AND WAVEGUIDES

(Regulation 2008)

Time : Three hours Maximum : 100 Marks

Answer ALL questions

PART A � (10 � 2 = 20 Marks)

1. A constant-K T-section high pass filter has a cutoff frequency of 10 KHz. The design impedance is 600 ohms. Determine the value of L.
2. What are the advantages of m-derived filters?
3. Define delay distortion.
4. Write the expressions for the phase constant and velocity of propagation for telephone cable.
5. A lossless line has a characteristic impedance of 400 ohms. Determine the standing wave ratio if the receiving end impedance is 800 +j 0.0 ohms. 6. Write the expressions for the input impedance of open and short circuited dissipationless line.
7. Define the cutoff frequency for the guided waves.
8. For a frequency of 6 GHz and plane separation of 3 cm, find the group and phase velocities for the dominant mode.
9. Calculate the cutoff wavelength for the TM11 mode in a standard rectangular waveguide if a = 4.5 cm.
10. Give the applications of cavity resonators.

PART B � (5 � 16 = 80 Marks)

11. (a) (i) Design a m-derived T-section low pass filter having a cutoff frequency (fc) of 5000 Hz and a design impedance of 600 ohms. The frequency of infinite attenuation is 1.25 fc. (8)
(ii) Draw and explain the operation of crystal filters. (8)

Or

(b) (i) Design a constant-K T-section bandpass filter with cutoff frequencies of 1 KHz and 4 KHz. The design impedance is 600 ohms. (8)
(ii) Draw a constant-K T-section band elimination filter and explain the operation with necessary design equations. (8)
12. (a) (i) A transmission line has the following per unit length parameters : L = 0.1� H, R =5 ohms, C = 300 pF and G = 0.01 mho. Calculate the propagation constant and characteristic impedance at 500 MHz. (8)
(ii) Derive the conditions required for a distortionless line. (8)

Or

(b) (i) The characteristic impedance of a uniform transmission line is 2309.6 ohms at a frequency of 800 MHz. At this frequency, the propagation constant is 0.054(0.0366 + j 0.99). Determine Rand L. (6)
(ii) Explain the reflection on lines not terminated in characteristic impedance with phasor diagrams. Define reflection coefficient and reflection loss. (10)
13. (a) (i) Draw and explain the operation of quarter wave line. (8) (ii) It is required to match a 200 ohms load to a 300 ohms transmission line to reduce the SWR along the line to 1. What must be the characteristic impedance of the quarter wave transformer used for this purpose if it is directly connected to the load? (4)
(iii) What are the drawbacks of single stub matching and open circuited stubs? (4)

Or

(b) (i) Draw and explain the principle of double stub matching. (8)
(ii) A UHF lossless transmission line working at 1 GHz is connected to an unmatched line producing a voltage reflection coefficient of 0.5(0.866 + j 0.5). Calculate the length and position of the stub to
match the line. (8)
14. (a) (i) Explain the transmission of TE waves between parallel perfectly conducting planes with necessary expressions and diagrams for the field components. (12)
(ii) A TEM wave at 1 MHz propagates in the region between conducting planes which is filled with dielectric material of r � = 1 and r e = 2. Find the phase constant and characteristic wave impedance. (4)

Or

(b) (i) Explain the reasons for the attenuation of TE and TM waves between parallel planes with necessary expressions and diagrams. (10)
(ii) Write a brief note on the manner of wave travel and their velocities between parallel planes. (6)
15. (a) (i) Discuss the propagation of TM waves in a rectangular waveguide with relevant expressions and diagrams for the field components. (10)
(ii) A rectangular waveguide measuring a = 4.5 cm and b = 3 cm internally has a 9 GHz signal propagated in it. Calculate the guide wavelength, phase and group velocities and characteristic impedance for the dominant mode. (6)

Or

(b) Explain the propagation of electromagnetic waves in a cylindrical waveguide with suitable expressions.(16)

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LINEAR INTEGRATED CIRCUITS MAY/JUNE 2012 QUESTION PAPER

B.E/B.Tech. DEGREE EXAMINATION, MAY/JUNE 2012.
Fourth Semester .
Electronics and Communication Engineering

LINEAR INTEGRATED CIRCUITS

(Common to PTEC 2254 Linear Integrated Circuits for B.E.(Part -Time) - ThirdSemester ECE - Regulation 2009)
(Regulation 2008)
Subject Code : EC 2254/l47404/EC 44/10144 EC 405/EC 1254/080290022
Subject Name : LINEAR INTEGRATED CIRCUITS
Time : Three hours                                                                          Maximum: 100 marks
Answer ALL questions

PART A�(lOx2= 2Omarks)

1. What are the two requirements to be met for a good current source?
2. List the various methods of realizing high input resistance in a differential amplifier.
3. Why active guard drive is necessary for an instrumentation amplifier?
4. What is comparator?
5. What are the advantages of variable transconductance technique?
6. VCO is also called as V-f converter. Why?
7. Define settling time of D/A converter.
8. What is the main drawback of dual slope ABC?
9. What are the limitations of three terminal regulator? .
10. What is a switched capacitor filter?

PART B � (5 x 16 = 80 marks)

11. (a) (i) With neat circuit diagrams, explain the operation of
(1) voltage reference circuit using temperature compensation
(2) voltage reference circuit using avalanche diode reference.                (12)
(ii) The current mirror shown below, is to provide a 1 mA current with Vcc = 10V.Assume � 125 and VBE = 0.7V.
(1) Determine the value of R1
(2) Also, for a collector current of 10 micro amperes, find the value of R1.             (4)
Or
(b) (i) List and explain the non-ideal DC characteristics of an operational amplifier. (8)
(ii) Explain the AC characteristics of an operational amplifier.
12. (a) (i) Sketch the basic circuit using op-amp to perform the mathematical operation of differentiation and explain. What are the limitations of an ordinary OP-AMP differentiator? Draw and explain the circuit of
a practical differentiators that will eliminate these limitations. (8)
(ii) Draw and explain the circuit of a voltage to current converter if the load is
(1) Floating
(2) Grounded.
Or
(b) (i) Explain the working of OP-AMP based Schmitt trigger circuit. (8)
(ii) Design an OP-AMP based second order active low pass filter with cut offfrequency 2 kHz. (8)
13. (a) (i) List and define the various performance parameters of a Multiplier IC. (6)
(ii) How the multiplier is used as voltage divider? (5)
(iii) How the multiplier is used as frequency doubler? (5)
Or
(b) Explain, with neat block diagrams, how PLL is used as
(i) AM Detector . (5)
(ii) FM Detector . (5)
(iii) Frequency Synthesizer. (6)
14. (a) (i) Explain the following types of electronic switches used in D/A converter, with suitable diagrams:
(1) Totem pole MOSFET switch (4)
(2) CMOS inverter as a switch. . (4)
(ii) Explain the working of R-2R ladder DAC, by taking example of a 3-bit DAC circuit. Sketch the corresponding equivalent circuits and hence obtain the equation for output. (8)
Or
(b) (i) With neat circuit diagram and wave form of output, explain the working of Dual slope A/D converter. (10)
(ii) Give a table of comparison of Flash, Dual-slope and Successive approximation ADCs, in terms of parameters like speed, accuracy, resolution, input-hold-time. (6)
15. (a) Sketch the functional block diagram of the following and explain their working principle:
(i) IC 555 Timer. (8)
(ii) General purpose voltage regulator IC 723. (8)
Or
(b) (i) With neat diagram, explain the working principle of isolation amplifier. (8)
(ii) With neat diagram, explain the principle of operation of optocouplers. (8)

MICROPROCESSORS AND MICROCONTROLLERS EC2304 ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER NOV/DEC 2011

Microprocessors and Microcontrollers EC2304  

ANNA UNIVERSITY EXAMINATIONS

NOV/DEC 2011  Question Paper

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EC2304 MICROPROCESSOR AND MICRO CONTROLLERS ANNA UNIVERSITY APRIL/MAY 2011 QUESTION PAPER

B.E/B.Tech. DEGREE EXAMINATION, APRIL/MAY 2011

FIFTH SEMESTER

ELECTRONICS AND COMMUNICATION ENGINEERING

EC2304- MICROPROCESSOR AND MICRO CONTROLLERS

(Regulation 2008)

PART-A [2*10=20]

1. When the 8086 processor is in minimum mode and maximum mode?
2. Define Segment Override Prefix.
3. What are the 8086 instructions used for BCD arithmetic? 
4. List any four program control instructions available in 8086?
5. What do you mean by sample and hold circuit?
6. List the major functions performed by CRT interface?
7. What happens in power down mode of 8051 microcontroller?
8. What are the different ways of operand addressing in 8051?
9. Why are relays that use coils called electromagnetic relays?
10. What is PWM?

PART-B

11.(a) (i) Explain the internal hardware architecture of 8086 microprocessor with neat diagram. [Marks 12]
(ii) Write briefly about the Direct Memory Access. [[Marks 4]

(or)

(b) (i) Explain the external memory addressing in 8086 [Marks 8]
(ii) Discuss the interrupts types of 8086 microprocessor. [Marks 8]

12.(a) (i) Explain the assembler directives ASSUME,EQU,DW,and EVEN with suitable examples. [Marks 8]
(ii) Write an 8086 ALP to sort the array of elements in ascending order. [Marks 8]

(or)

(b) (i) Write an 8086 ALP to find the largest element in an array elements. [Marks 6]
(ii) Explain the data transfer group and logical group of 8086 instructions. [Marks 10]

13.(a) With neat block diagram explain the 8255 Programmable Peripheral Interface and its operating modes. [Marks 16]

(or)

(b) Draw and explain the block diagram of 8254 Programmable Interval Timer. Also explain the various modes of operation. [Marks 16]

14.(a) (i) Explain the architecture of 8051 microcontroller with neat diagram. [Marks 12]
(ii) Write briefly about the operating modes for serial port of 8051 microcontroller. [Marks 4]

(or)

(b) (i) Write an 8051 ALP to create a square wave of 66% duty cycle on bit 3 of port 1. [Marks 6]
(ii) Describe the different modes of operation of timers/counters in 8051 with its associated register. [Marks 10]

15.(a) (i) Draw and explain the block diagram of traffic light control system. [Marks 10]
(ii) Briefly discuss the features of RTC device. [Marks 6]

(or)

(b) Draw the diagram to interface a stepper motor with 8051 microcontroller and explain. Also write an 8051 ALP to run the stepper motor in both forward and reverse direction with delay. [Marks 16]

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EC2304 MICROPROCESSOR AND MICRO CONTROLLERS ANNA UNIVERSITY NOV/DEC 2010 QUESTION PAPER

B.E/B.Tech. DEGREE EXAMINATION, Nov/Dec 2010

FIFTH SEMESTER

ELECTRONICS AND COMMUNICATION ENGINEERING

EC2304- MICROPROCESSOR AND MICRO CONTROLLERS

(Regulation 2008)

PART-A(10*2=20marks)

1.What are tri-state devices?
2.Mention the advantages of using the Direct Memory Access.
3.What is the purpose of the following commands in 8086?(a)AAD,(b)RCL
4.Write an 8086 assembly language program to multiply two 16 bit unsigned numbers to provide a 32 bit result.Assume that the two numbers are stored in CX and DX.
5.Give the salient features of the 8254 Programmable interval timer.
6.What is a Sample and Hold circuit?
7.What are the advantages of the register indirect addressing mode in 8051 microcontroller?
8.Write an 8051 program to monitor PI continuously for the value 63H.It should get out of the monitoring only if P1=63H.
9.How is the microcontroller used for the traffic light control application?
10.Differentiate microprocessor from microcontroller in system design.

PART B (5 16 = 80 Marks)

11(a)(i)Explain the 8085 bus structure with a neat sketch.
(ii)What are the peripheral I/O instructions?Write its syntax and explain the same with the timing diagram.

or

(b)Explain the 8086 interrupts types in detail.

12(a)Explain the 8086 bit manipulation instructions with an example for each.

or

(b)Write an 8086 program to convert BCD data to binary data.

13(a)Explain the 8279 keyboard and sisplay controller with a neat sketch.

or

(b)Describe the architecture and working of 8253 timer.

14(a)Assume that 5 BCD data items are stored in RAM locations starting at 40H as shown below.Write an 8051 program to find the sum of all the numbers.The result must be in BCD.
40=(71),41=(11),42=(65),43=(59),44(37)

or

(b)Explain the working of the 8051 microcontroller.Give a neat sketch.

15(a)Explain how microcontrollers and microprocessors can be used for the washing machine control application.Use sketches.

or

(b)Explain with a neat sketch how microcontrollers and microprocessors can be used for the stepper motor control application.

DIGITAL SIGNAL PROCESSING EC2302 APRIL/MAY 2011 ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, April/May 2011

Fifth Semester

Electronics and Communication Engineering

EC 2302 DIGITAL SIGNAL PROCESSING

(Regulation 2008)

Time : Three hours Maximum : 100 Marks

Answer ALL questions

PART A (10 2 = 20 Marks)

1.State the advantages of FFT over DFTs.
2.What is mean by bit reversal?
3.Why do we go for analog approximation to deisgn a digital filter?
4.Give any two properties of chebyshev filters.
5.State the properties of FIR filters.
6.What is mean by Gibbs phenomenon?
7.What is mean by fixed point arithmetic?Give example.
8.Explain the meaning of limit cycle oscillator.
9.State the various applications of DSP.
10.What is echo cancellation?

PART B (5 16 = 80 Marks)

11(a)With appropriate diagrams describe (i)overlap-save method,(ii)overlap-add method.

or

(b)Explain Radix-2 DIF-FFT algorithm.Compare it with DIT-FFT algorithms.
12(a)Explain in detail Butterworth filter approximation.

or

(b)Expalin the bilinear transform method of IR filter design.What is warping effect?Explain the poles and zeros mapping procedure clearly.
13(a)Realize the system function H(z)=(2/3)z+1+(2/3)z(to the power -1) by linear phase FIR structure.

or

(b)Explain the designing of FIR filters using windows.
14(a)Explain the quantization process and errors introduced due to quantisation.

or

(b)(i)Explain how reduction of product round-off error is achieved in digital filters.
(ii)Explain the effects of coefficient quantisation in FIR filters.
15(a)(i)Explain how various sound effects can be generated with the help of DSP.
(ii)State the applications of multirate signal processing.

or

(b)(i)Expalin how DSP can be used for speech processing.
(ii)Explain in detail about decimation and interpolation.

DIGITAL SIGNAL PROCESSING EC2302 ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION NOVEMBER/DECEMBER 2010 

 Fifth Semester 

 Electronics and Communication Engineering 

 EC 2302 � DIGITAL SIGNAL PROCESSING

DOWNLOAD QP HERE 

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ANNA UNIVERSITY NOV/DEC 2011 EC2301 DIGITAL COMMUNICATION QUESTION PAPER DOWNLOAD

EC2301 DIGITAL COMMUNICATION APRIL/MAY 2011 ANNA UNIVERSITY PREVIOUS YEAR QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, April/May 2011

Fifth Semester

Electronics and Communication Engineering

EC 2301 DIGITAL COMMUNICATION

(Regulation 2008)

Time : Three hours Maximum : 100 Marks

Answer ALL questions

PART A (10*2 = 20 Marks)

1.Give an example each for time limited and time unlimited signals.
2.Give an advantage and a disadvantage of digital communication.
3.State sampling theorem.
4.What is quantization error?
5.Define hamming distance.
6.What is mean by transparency with respect to line codes?
7.What is a matched filter?
8.Give two applications for eye pattern.
9.Draw the PSK waveform for 011011.
10.What is a non-coherent detection system?

PART B (5*16 = 80 Marks)

11(a)Explain how PWM and PPM signals are generated.

or

11(b)(i)Classify channels.Explain the mathematical model of any two communication channels.(6)
(ii)Explain Binary symmetric channel and Gaussian channel with
their mathematical models. (Marks 10)

12(a)(i)Explain a non-uniform quantization process.
(ii)Write notes on temporal waveform coding.

or

12(b)(i)Explain a spectral waveform encoding porcess.
(ii)Compare various speeches encoding methods.

(13)(a)(i)Assume a (2,1) convolutional coder with constraint length 6.Draw the tree diagram,state diagram and trellis diagram for the assumed coder.
(ii)Find the (7,4) linear systematic block code word corresponding to 1101.Assume a suitable generator matrix.

or

13(b)Draw the power spectra of polar codes and on-off codes.Discuss their characteristics.

14(a)Derive the expression for bit error probability due to a matched filter.

or

(b)Disucss on signal design for ISI elimination.

15(a)Derive the bit error probability due to coherent ASK,PSK and FSK systems.Compare the performance of these systems.

or

15(b)(i)Disucss QPSK signalling
(b)(ii)Derive the bit error probability due to QPSK receiver.Compare the performance of QPSK receiver with that of PSK receiver.

DIGITAL COMMUNICATION EC2301 ANNA UNIVERSITY NOV/DEC 2010 PREVIOUS YEAR QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2010
Fifth Semester
Electronics and Communication Engineering
EC 2301 � DIGITAL COMMUNICATION
(Regulation 2008)
Time : Three hours Maximum : 100 Marks
Answer ALL questions
PART A � (10 � 2 = 20 Marks)

1. Which parameter is called figure of merit of a digital communication system and why?
2. What is meant by distortion less transmission?
3. Why is prefiguring done before sampling?
4. Define quantization noise power.
5. Define Hamming distance and calculate its value for two code words 11100 and 11011.
6. Draw the NRZ and RZ code for the digital data 10110001.
7. What is the need for a demodulator in case of base band signaling when the received waveforms are already in pulse like form?
8. How does pulse shaping reduce inter symbol interference?
9. Define QAM and draw its constellation diagram.
10. A binary frequency shift keying system employs two signaling frequencies 1 f and 2 f . The lower frequency 1 f is 1200 Hz and signaling rate is 500 Baud.Calculate 2 f .

PART B � (5 � 16 = 80 Marks)

11. (a) Draw a neat block diagram of a typical digital communication system and explain the function of the key signal processing blocks. (Marks 16)
Or
(b) (i) Distinguish between base band and bandpass signaling. (Marks 6)
(ii) Explain Binary symmetric channel and Gaussian channel with their mathematical models. (Marks 10)
12. (a) State the Nyquist sampling theorem. Demonstrate its validity for an analog signal x(t) having a Fourier transform x( f ) which is zero outside the interval [ ] m m - f < f < +f (Marks 16)

Or
(b) Explain in detail the various source coding techniques for speech signal and compare their performance. (16)
13. (a) For (6,3) systematic linear block code, the code word comprises 1 I , 2 I , 3 I , 1 P , 2 P , 3 P where the three parity check bits 1 P , 2 P and 3 P are formed from the information bits as follows : (16)
P1 = I1 ? I2
P2 = I1 ? I3
P3 = I2 ? I3
Find
(i) The parity check matrix
(ii) The generator matrix
(iii) All possible code words.
(iv) Minimum weight and minimum distance and
(v) The error detecting and correcting capability of the code.
(vi) If the received sequence is 10,000.
Calculate the syndrome and decode the received sequence.
Or
(b) (i) Explain how encoding is done by convolution codes with a suitable example. (Marks 10)
(ii) Explain tree diagram, trellis diagram and state transition diagram of convolution codes. (Marks 6)

14. (a) (i) Define a matched filter and compare its functioning with a correlation. (Marks 10)
(ii) Explain how a matched filter can maximize SNR for a given transmitted symbol. (Marks 6)
Or
(b) What does the term equalization refer to? Explain how it is carried out by using transverse filters. (Marks 16)
15. (a) (i) Distinguish coherent and non-coherent detection. (Marks 4)
(ii) Explain non-coherent detection methods of binary frequency shift keying scheme. (Marks 12)
Or
(b) (i) Explain Binary PSK and QPSK with corresponding equations and constellation diagrams. (Marks 8)
(ii) Obtain the probability of bit error for coherently detected BPSK and compare its probability of bit error performance with QPSK scheme. (Marks 8)

EC2402 OPTICAL COMMUNICATION AND NETWORKING PREVIOUS YEAR ANNA UNIVERSITY QUESTION PAPER /MODEL QUESTION PAPER NOV/DEC 2011

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2011.

Seventh Semester

Electronics and Communication Engineering

EC 2402 � OPTICAL COMMUNICATION AND NETWORKING

(Regulation 2008)

Time : Three hours Maximum : 100 marks

Missing data could be suitably assumed.

Answer ALL questions.

PART A � (10 � 2 = 20 marks)

1. What is the energy of a single photon of the light whose ? = 1550 nm, in eV?

2. Assume that there is a glass rod of refractive index 1.5, surrounded by air. Find the critical incident angle.

3. Define the attenuation coefficient of a fiber.

4. Calculate the cut-off wavelength of an optical signal through a fiber with its core refractive index of 1.50 and that of cladding = 1.46. The core radius of 25 �m. The normalised frequency is 2.405.

5. Why silicon is not used to fabricate LED or Laser diode?

6. Calculate the external differential quantum efficiency of a laser diode operating at 1.33 �m. The slope of the straight line portion of the curve for the emitted optical power P versus drive current I is given by 15 mW/mA.

7. Define �quantum efficiency� of a photo detector and write the expression.

8. Mention the error sources in fiber optic receiver.

9. What are the three common topologies used for fiber optical network? Give the schematic of any one network?

10. Calculate the number of independent signals that can be sent on a single fiber in the 1525-1565 nm band. Take the spectral spacing as per ITU-T recommendation G.692.

PART B � (5 � 16 = 80 marks)

11. (a) (i) What is numerical aperture of an optical fiber? Deduce an expression for the same. (12)

(ii) Calculate NA of silica fiber with its core refractive index (n1) of 1.48 and cladding refractive index of 1.46. What should be the new value of �n1� in order to change the NA to 0.23. (4)

Or

(b) (i) Explain the phenomenon of total internal reflection using Snell's law with figures and calculations. (12)

(ii) Distinguish step-index from graded index fibers. (4)

12. (a) (i) What do you mean by pulse broadening? Explain its effect on information carrying capacity of a fiber. (12)

(ii) An LED operating at 850 nm has a spectral width of 45 nm. What is the pulse spreading in ns/km due to material dispersion? What is the pulse spreading when a laser diode having a 2 nm spectral width is used? The material dispersion is 90 ps/nm km. (4)

Or

(b) (i) What is meant by �fiber splicing�? Explain fusion splicing of optical fibers. (8)

(ii) Explain expanded beam fiber connector with a neat schematic.(8)

13. (a) (i) Compare LED with a laser diode. (4)

(ii) With the help of a neat diagram explain the construction and working of a surface emitting LED. (12)

Or

(b) (i) Explain the structure and working of a silicon APD. (12)

(ii) Define S/N ratio of a photodetector. What conditions should be met to achieve a high SNR? (4)

14. (a) (i) Explain the fiber optic receiver operation using a simple model and its equivalent circuit. (8)

(ii) Explain the operation of a pre-amplifier built using a FET. (8)

Or

(b) Explain the measurement technique used in the case of

(i) Numerical aperture

(ii) Refractive index profile

(iii) Fiber cut-off wave length

(iv) Fiber diameter. (16)

15. (a) Explain the architecture of SONET and discuss nonlinear effects on Network performance. (16)

Or

(b) Write short notes on

(i) Wavelength routed networks. (8)

(ii) Optical CDMA. (8)

HOW YOU DID YOUR EC2151-ECED RE-EXAM TODAY : DROP YOUR COMMENTS HERE

Anna University, Chennai Conducted ECED re-examination today(31.07.2012) for first year students and higher semester students who got Arrear in ECED , so here you can find the question paper here what you got in your hands around 10 Am Today 

Though some guesses where there that question paper will be difficult, and later by 1 Pm we got the feedback that questions where actually moderate. So students you can post your comments here, so that we can share your feedback here @ rejinpaul.com 

PRINCIPLES OF MANAGEMENT MG2351 ANNA UNIVERSITY NOVEMBER/DECEMBER 2011 QUESTION PAPER

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2011.

Seventh Semester

Electrical and Electronics Engineering

MG 2351 � PRINCIPLES OF MANAGEMENT

(Common to Seventh Semester � Polymer Technology, Textile Technology,

Textile Technology (Fashion Technology) and common to Sixth Semester

Aeronautical Engineering, Automobile Engineering, Civil Engineering,

Electronics and Communication Engineering and Mechanical Engineering)

(Regulation 2008)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A � (10 � 2 = 20 marks)

1. What are the various functions of management?

2. What is scientific management?

3. What is the main purpose of planning?

4. Define the term strategic planning.

5. What is division of labour?

6. Define the term functional authority.

7. What is non-verbal communication?

8. Define Job enlargement.

9. List the basic types of control.

10. What are the three potential pitfalls of budgets?

PART B � (5 � 16 = 80 marks)

11. (a) Explain in detail Henry Fayol�s contribution towards classical approach towards management.

Or

(b) (i) Describe the relative importance of each type of the skills to lower, middle and upper level managers. (8)

(ii) Explain the system based approach towards the management.(8)

12. (a) (i) Discuss the types and steps involved in decision making process. (8)

(ii) Explain Business portfolio matrix. (8)

Or

(b) (i) Describe in detail the various types of organizational plans. (8)

(ii) What are the different types decision and decision-making processes? (8)

13. (a) What do you understand by organizational chart? Explain the basis of the departmentalization.

Or

(b) Discuss the steps involved in providing appropriate human resources.

14. (a) (i) Explain the types of formal organizational communications. (8)

(ii) Discuss the barriers of effective interpersonal communications.(8)

Or

(b) Does motivation important for organization development/achievement? Justify your answer with Maslow�s hierarchy of needs.

15. (a) Explain the term operations management and major activities associated with operations management.

Or

(b) Discuss briefly the tools for organizational control.

WIRELESS COMMUNICATION EC2401 ANNA UNIVERSITY PREVIOUS YEAR MODEL QUESTION PAPER FOE ECE

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2011.

Seventh Semester

Electronics and Communication Engineering

EC 2401 � WIRELESS COMMUNICATION

(Regulation 2008)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A � (10 � 2 = 20 marks)

1. Differentiate Cellular telephony and Cordless telephony.

2. When does a WLAN become a personal Area Network (PAN)?

3. Compute the Rayleigh distance of a square Antenna with 20 dB gain.

4. List out any two properties of wideband channel.

5. Draw the mathematical link model for analysis of modulation schemes.

6. What is OQPSK?

7. Mention any four common methods of micro diversity.

8. Define Hamming distance and Euclidean distance between two codes.

9. Discuss the principle of OFDM modulation scheme.

10. Give three important functional blocks of GSM system.

PART B � (5 � 16 = 80 marks)

11. (a) (i) Compare and contrast wired and wireless communication. (8)

(ii) Discuss briefly about the requirements of services for a wireless system. (8)

Or

 (b) (i) Discuss in detail the constructive and destructive interference.(8)

(ii) Explain how Inter Symbol Interference is caused and how it is eliminated. (8)

12. (a) (i) Describe any two methods of diffraction by multiple screens. (8)

(ii) Discuss about ultra wide band channel. (8)

Or

(b) (i) Compare Coherence Bandwidth and Coherence time (8)

(ii) Discuss the mathematical formulation for narrowband and wideband system, with relevant figures. (8)

13. (a) Compute the ratio of signal power to adjacent channel interference

When using (i) raised cosine pulses (ii) root raised cosine pulses with a = 0.5, when two considered signals have center frequencies 0 and 1.25/ T. (16)

Or

(b) (i) Discuss in detail any two demodulation techniques of minimum shift keying method. (8)

(ii) Explain in detail about optimum receiver structure for Non-coherent detection. (8)

14. (a) Explain the Viterbi decoding scheme if the decoder input sequence is �010 000 100 001 011 110 001�. (16)

Or

(b) (i) With a neat block diagram discuss the structure of a decision feedback equalizer. (8)

(ii) Discuss linear predictive vocoder with block diagram. (8)

15. (a) (i) Explain the principle of direct sequence spread spectrum technique.

(8)

(ii) Discuss some methods to increase the capacity of wireless communication system. (8)

Or

(b) (i) Explain in detail about the GSM logical channels. (8)

(ii) Explain the block diagram of IS-95 transmitter. (8)